OpenZFS 7431 - ZFS Channel Programs

Authored by: Chris Williamson <[email protected]>
Reviewed by: Matthew Ahrens <[email protected]>
Reviewed by: George Wilson <[email protected]>
Reviewed by: John Kennedy <[email protected]>
Reviewed by: Dan Kimmel <[email protected]>
Approved by: Garrett D'Amore <[email protected]>
Ported-by: Don Brady <[email protected]>
Ported-by: John Kennedy <[email protected]>

OpenZFS-issue: https://www.illumos.org/issues/7431
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/dfc11533

Porting Notes:
* The CLI long option arguments for '-t' and '-m' don't parse on linux
* Switched from kmem_alloc to vmem_alloc in zcp_lua_alloc
* Lua implementation is built as its own module (zlua.ko)
* Lua headers consumed directly by zfs code moved to 'include/sys/lua/'
* There is no native setjmp/longjump available in stock Linux kernel.
  Brought over implementations from illumos and FreeBSD
* The get_temporary_prop() was adapted due to VFS platform differences
* Use of inline functions in lua parser to reduce stack usage per C call
* Skip some ZFS Test Suite ZCP tests on sparc64 to avoid stack overflow

1 files changed, 229 insertions, 0 deletions

diff --git a/module/lua/lstate.h b/module/lua/lstate.h
new file mode 100644
index 000000000..22e575e9a
--- /dev/null
+++ b/module/lua/lstate.h
@@ -0,0 +1,229 @@
+/* BEGIN CSTYLED */
+/*
+** $Id: lstate.h,v 2.82.1.1 2013/04/12 18:48:47 roberto Exp $
+** Global State
+** See Copyright Notice in lua.h
+*/
+
+#ifndef lstate_h
+#define lstate_h
+
+#include <sys/lua/lua.h>
+
+#include "lobject.h"
+#include "ltm.h"
+#include "lzio.h"
+
+
+/*
+
+** Some notes about garbage-collected objects:  All objects in Lua must
+** be kept somehow accessible until being freed.
+**
+** Lua keeps most objects linked in list g->allgc. The link uses field
+** 'next' of the CommonHeader.
+**
+** Strings are kept in several lists headed by the array g->strt.hash.
+**
+** Open upvalues are not subject to independent garbage collection. They
+** are collected together with their respective threads. Lua keeps a
+** double-linked list with all open upvalues (g->uvhead) so that it can
+** mark objects referred by them. (They are always gray, so they must
+** be remarked in the atomic step. Usually their contents would be marked
+** when traversing the respective threads, but the thread may already be
+** dead, while the upvalue is still accessible through closures.)
+**
+** Objects with finalizers are kept in the list g->finobj.
+**
+** The list g->tobefnz links all objects being finalized.
+
+*/
+
+
+struct lua_longjmp;  /* defined in ldo.c */
+
+
+
+/* extra stack space to handle TM calls and some other extras */
+#define EXTRA_STACK   5
+
+
+#define BASIC_STACK_SIZE        (2*LUA_MINSTACK)
+
+
+/* kinds of Garbage Collection */
+#define KGC_NORMAL	0
+#define KGC_EMERGENCY	1	/* gc was forced by an allocation failure */
+#define KGC_GEN		2	/* generational collection */
+
+
+typedef struct stringtable {
+  GCObject **hash;
+  lu_int32 nuse;  /* number of elements */
+  int size;
+} stringtable;
+
+
+/*
+** information about a call
+*/
+typedef struct CallInfo {
+  StkId func;  /* function index in the stack */
+  StkId	top;  /* top for this function */
+  struct CallInfo *previous, *next;  /* dynamic call link */
+  short nresults;  /* expected number of results from this function */
+  lu_byte callstatus;
+  ptrdiff_t extra;
+  union {
+    struct {  /* only for Lua functions */
+      StkId base;  /* base for this function */
+      const Instruction *savedpc;
+    } l;
+    struct {  /* only for C functions */
+      int ctx;  /* context info. in case of yields */
+      lua_CFunction k;  /* continuation in case of yields */
+      ptrdiff_t old_errfunc;
+      lu_byte old_allowhook;
+      lu_byte status;
+    } c;
+  } u;
+} CallInfo;
+
+
+/*
+** Bits in CallInfo status
+*/
+#define CIST_LUA	(1<<0)	/* call is running a Lua function */
+#define CIST_HOOKED	(1<<1)	/* call is running a debug hook */
+#define CIST_REENTRY	(1<<2)	/* call is running on same invocation of
+                                   luaV_execute of previous call */
+#define CIST_YIELDED	(1<<3)	/* call reentered after suspension */
+#define CIST_YPCALL	(1<<4)	/* call is a yieldable protected call */
+#define CIST_STAT	(1<<5)	/* call has an error status (pcall) */
+#define CIST_TAIL	(1<<6)	/* call was tail called */
+#define CIST_HOOKYIELD	(1<<7)	/* last hook called yielded */
+
+
+#define isLua(ci)	((ci)->callstatus & CIST_LUA)
+
+
+/*
+** `global state', shared by all threads of this state
+*/
+typedef struct global_State {
+  lua_Alloc frealloc;  /* function to reallocate memory */
+  void *ud;         /* auxiliary data to `frealloc' */
+  lu_mem totalbytes;  /* number of bytes currently allocated - GCdebt */
+  l_mem GCdebt;  /* bytes allocated not yet compensated by the collector */
+  lu_mem GCmemtrav;  /* memory traversed by the GC */
+  lu_mem GCestimate;  /* an estimate of the non-garbage memory in use */
+  stringtable strt;  /* hash table for strings */
+  TValue l_registry;
+  unsigned int seed;  /* randomized seed for hashes */
+  lu_byte currentwhite;
+  lu_byte gcstate;  /* state of garbage collector */
+  lu_byte gckind;  /* kind of GC running */
+  lu_byte gcrunning;  /* true if GC is running */
+  int sweepstrgc;  /* position of sweep in `strt' */
+  GCObject *allgc;  /* list of all collectable objects */
+  GCObject *finobj;  /* list of collectable objects with finalizers */
+  GCObject **sweepgc;  /* current position of sweep in list 'allgc' */
+  GCObject **sweepfin;  /* current position of sweep in list 'finobj' */
+  GCObject *gray;  /* list of gray objects */
+  GCObject *grayagain;  /* list of objects to be traversed atomically */
+  GCObject *weak;  /* list of tables with weak values */
+  GCObject *ephemeron;  /* list of ephemeron tables (weak keys) */
+  GCObject *allweak;  /* list of all-weak tables */
+  GCObject *tobefnz;  /* list of userdata to be GC */
+  UpVal uvhead;  /* head of double-linked list of all open upvalues */
+  Mbuffer buff;  /* temporary buffer for string concatenation */
+  int gcpause;  /* size of pause between successive GCs */
+  int gcmajorinc;  /* pause between major collections (only in gen. mode) */
+  int gcstepmul;  /* GC `granularity' */
+  lua_CFunction panic;  /* to be called in unprotected errors */
+  struct lua_State *mainthread;
+  const lua_Number *version;  /* pointer to version number */
+  TString *memerrmsg;  /* memory-error message */
+  TString *tmname[TM_N];  /* array with tag-method names */
+  struct Table *mt[LUA_NUMTAGS];  /* metatables for basic types */
+} global_State;
+
+
+/*
+** `per thread' state
+*/
+struct lua_State {
+  CommonHeader;
+  lu_byte status;
+  StkId top;  /* first free slot in the stack */
+  global_State *l_G;
+  CallInfo *ci;  /* call info for current function */
+  const Instruction *oldpc;  /* last pc traced */
+  StkId stack_last;  /* last free slot in the stack */
+  StkId stack;  /* stack base */
+  int stacksize;
+  unsigned short nny;  /* number of non-yieldable calls in stack */
+  unsigned short nCcalls;  /* number of nested C calls */
+  lu_byte hookmask;
+  lu_byte allowhook;
+  int basehookcount;
+  int hookcount;
+  lua_Hook hook;
+  GCObject *openupval;  /* list of open upvalues in this stack */
+  GCObject *gclist;
+  struct lua_longjmp *errorJmp;  /* current error recover point */
+  ptrdiff_t errfunc;  /* current error handling function (stack index) */
+  CallInfo base_ci;  /* CallInfo for first level (C calling Lua) */
+};
+
+
+#define G(L)	(L->l_G)
+
+
+/*
+** Union of all collectable objects
+*/
+union GCObject {
+  GCheader gch;  /* common header */
+  union TString ts;
+  union Udata u;
+  union Closure cl;
+  struct Table h;
+  struct Proto p;
+  struct UpVal uv;
+  struct lua_State th;  /* thread */
+};
+
+
+#define gch(o)		(&(o)->gch)
+
+/* macros to convert a GCObject into a specific value */
+#define rawgco2ts(o)  \
+	check_exp(novariant((o)->gch.tt) == LUA_TSTRING, &((o)->ts))
+#define gco2ts(o)	(&rawgco2ts(o)->tsv)
+#define rawgco2u(o)	check_exp((o)->gch.tt == LUA_TUSERDATA, &((o)->u))
+#define gco2u(o)	(&rawgco2u(o)->uv)
+#define gco2lcl(o)	check_exp((o)->gch.tt == LUA_TLCL, &((o)->cl.l))
+#define gco2ccl(o)	check_exp((o)->gch.tt == LUA_TCCL, &((o)->cl.c))
+#define gco2cl(o)  \
+	check_exp(novariant((o)->gch.tt) == LUA_TFUNCTION, &((o)->cl))
+#define gco2t(o)	check_exp((o)->gch.tt == LUA_TTABLE, &((o)->h))
+#define gco2p(o)	check_exp((o)->gch.tt == LUA_TPROTO, &((o)->p))
+#define gco2uv(o)	check_exp((o)->gch.tt == LUA_TUPVAL, &((o)->uv))
+#define gco2th(o)	check_exp((o)->gch.tt == LUA_TTHREAD, &((o)->th))
+
+/* macro to convert any Lua object into a GCObject */
+#define obj2gco(v)	(cast(GCObject *, (v)))
+
+
+/* actual number of total bytes allocated */
+#define gettotalbytes(g)	((g)->totalbytes + (g)->GCdebt)
+
+LUAI_FUNC void luaE_setdebt (global_State *g, l_mem debt);
+LUAI_FUNC void luaE_freethread (lua_State *L, lua_State *L1);
+LUAI_FUNC CallInfo *luaE_extendCI (lua_State *L);
+LUAI_FUNC void luaE_freeCI (lua_State *L);
+
+
+#endif
+/* END CSTYLED */